E. Bramanti et al., Application of mercury cold vapor atomic fluorescence spectrometry to the characterization of mercury-accessible -SH groups in native proteins, ANALYT BIOC, 274(2), 1999, pp. 163-173
A new analytical approach has been applied to the determination and charact
erization of mercury-accessible -SH groups in pure native protein samples (
ovalbumin, hemoglobin, glyceraldehyde-3-phosphate dehydrogenase, aldolase,
pyruvate kinase, hexokinase, lactate dehydrogenase, alcohol dehydrogenase,
creatine phosphokinase, lysozyme, and cytochrome c). The method is based on
the selective reduction of Hg-II in the presence of Hg-II-thiol complexes
with alkaline sodium tetrahydroborate, to give Hg-0 in a continuous flow re
action system coupled with atomic fluorescence spectrometric (AFS) detectio
n. The method is fast and specific and allows one to work with nanomole amo
unts of a single protein without any preliminary incubation and without any
separation of Hg-II from thiol-complexed mercury. The meaning of the resul
ts obtained in the determination of the accessible -SH groups in native pro
teins by using chemical probes is discussed. (C) 1999 Academic Press.